p.1 

OAR Box 1190 

Prepped by Candice Davis 

Document Number: 

41) ll-A-33 

Docket Number: 

A-90-28 

Printed 5/5/2008 9:13:51 AM Sheet 41 of 106 
P.2 

^ ^ 

ST/ * OFCALIFORNIA—CALIFORNIA ENVIRONMENTAL PROTECTION AGENCY PETE WILSON, Governor 

AIF? RESOURCES BOARD 

2020 L STREET 

P.O. BOX 2815 

SACRAMENTO. CA 95814-2815 

July 21, 1994 

Charles N. Freed, Director 

U.S. Environmental Protection Agency 

Manufacturers Operations Division 

401 M Street S.W. (6405J) 

Washington, D.C. 20460 

Dear Mr. Freed: 

This letter will confirm our telephone conversation during the week of June 27, 1994. 

During that conversation I explained that the Air Resources Board (ARB) would like to 

request that the hearing to consider California's request for a waiver for the on-board 

diagnostic (OBD II) regulations be delayed to on or about March 1995. This request is 

necessary because the ARB is in the process of proposing modifications to the regulations 

that will address many of the concerns that have been raised by industry and reflect recent 

developments in technology. 

I am enclosing for your information a copy of the workshop notice that is scheduled 

to be held on July 27 in El Monte. We are anticipating that the proposed modifications will 

be considered by the ARB in December of this year. After the modifications are considered, 

the ARB will supplement its waiver request addressing the substantive changes in the context 

of the federal waiver criteria. 

If you have any legal questions regarding this letter, please do not hesitate to call 

either myself or Michael Terris at (916) 322-2884. If you have any technical questions, 

please call Steve Albu, Chief, Engineering Studies Branch, Mobile Source Division, at (818) 

575-7010. Thank you for your understanding and assistance. 

Sincerely 

licnael P. Kenny 

General Counsel 

Attachment 

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93?8 TELSTAR AVENUE X^ ^ 

f l MO^TE, CA 91731-2990 

f -ONE: (818) 575-4800 

i June 23, 1994 

TO: ALL PASSENGER CAR MANUFACTURERS 

ALL LIGHT-DUTY/MEDIUM-DUTY VEHICLE MANUFACTURERS 

ALL OTHER INTERESTED PARTIES 

SUBJECT: ON-BOARD DIAGNOSTIC II (OBD II) REQUIREMENT UPDATE 

PacKgrcunti 

The Board originally adopted section 1968.1 of Title 13, California Code of Regulations, which 

contains the malfunction detection and diagnostic system requirements known as OBD II, on 

Je&temberJJ^9^ ^ 

regulation to promote consistency with the federal OBD requirements proposed at that time, to 

address manufacturers' concerns regarding OBD II implementation, and to improve the 

effectiveness of certain requirements. The regulation was also modified through amendments 

adopted July 9, 1993, to provide limited relief from the OBD II requirements during the 1994 

• •£-". •*9*fc."-«'nt«iluuab*<" .and. 19.95_roodel„y.ear^hasi^a^eriod,foatie .regulation^- cwvu<v<Ui«'aaiHi«.n

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Currently, a Board Hearing is scheduled for December, 1994, at which an update will be 

presented regarding manufacturers' progress toward successfully implementing OBD II 

systems on low-emission vehicle applications. Along with the update, other issues that will_ ', 

likely Be*addfessed ihclude~c^talystlfioh1toYrng issues,lhe 1997'model year"misfire detection" 

requirements, evaporative system leak detection, OBD II compliance on diesel applications and 

1996 model year compliance concerns. A number of minor modifications and clarifications will 

also be considered. The ARB staff has scheduled a workshop for Wednesday, July 27,1'994, 

from 9:00 A.M. to 5:00 P.M. to discuss these issues prior to the release of the public hearing 

notice and Staff Report. The Workshop will be held at: 

Air Resources Board 

Annex IV Auditorium 

9528 Telstar Ave 

El Monte, CA 91731 

The ARB's current position and proposals regarding the issues to be discussed are summarized 

below. 

Catalyst Monitoring 

The OBD II regulation specifies separate catalyst monitoring requirements for vehicles meeting 

emission standards prescribed by California's Low-Emission Vehicle regulation (identified in the 

regulation as LEVs), and those meeting less stringent emission.standards (nbn-LEVs). With 

respect to non-LEVs, catalyst system deterioration must be detected before emissions increase 

by 1.5 times the standard compared to the emission level using representative 4000 mile 

catalysts. Several manufacturers have already certified vehicles with catalyst monitoring 

systems meeting the non-LEV requirements. For LEVs, the regulation currently requires a 

malfunction to be indicated when front catalyst average Federal Test Procedure (FTP) 

hydrocarbon efficiency falls between 50 to 60 percent (meaning that only 50 to 60 percent of 

engine out hydrocarbons are converted), or ifthe front catalyst is classified as a small volume 

a 
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P.4 

standard, not added on to the 4000-mile emission level of the vehicle. The regulation included 

the 4000-mile emission level for non-LEVs to promote consistency with the federal OBD 

requirements. Manufacturers have suggested that the 4000-mile emission level should also be 

included for LEVs. This would allow for emissions to increase to as much as 2.5 times the 

standard before a malfunction is indicated. As a long term goal, the staff believes that such 

emission increases would be unacceptably high if California is to have hope of achieving 

mandated air qualify standards. 

For the manufacturers producing OBD Il-equipped TLEV applications for the 1995 model year, 

the staff does not believe that significant monitoring system design changes will be necessary 

to meet the proposed revised requirements. The ARB staff believes that with adequate catalyst 

volume downstream of the monitored front catalyst, tailpipe emissions should not significantly 

manufacturer producing a 1995 model year TLEV has stated it is confident that emissions will 

remain below 1.5 times the standard even when the front catalyst is deteriorated, and is 

planning to conduct testing to confirm this estimate. Emission testing conducted by the ARB in 

1992 also supports the staffs position. The test vehicle was a 1990 Buick LeSabre equipped 

.with.aa.el®ctriGally~heated.cat3ly^ 

system disconnected, the vehicle's catalyst system (i.e., a warm-up catalyst followed by a main 

catalyst) is representative of catalyst configurations currently in production on TLEVs. The 

emission performance ofthe vehicle without electrical heating (0.078 grams per mile NMOG) 

also indicates that for testing purposes, the vehiclej^asonably represents the performance of a 

production TLEV. When'tested with the front catalysTremoved,"emissions increased to only 

0.115 grams per mile, far below the 1.5 times the standard threshold of 0.188 grams per mile. 

The emission increase of only approximately 0.04 grams per mile with the catalyst completely 

removed further suggests that the emission threshold should be achievable at LEV and ULEV 

emission category levels as well. Further testing by t|ie,staff isjsjanned to providejddjtional 

data. However, despite these findings, if is possible that additional leadtime may be necessary 

for some manufacturers to make monitoring system adjustments to meet the 1.5 times the 

standard emission threshold for TLEVs, or to verify that the threshold will be met reliably in-use. 

For LEV and ULEV category levels, few if any such models will be produced before 1998 

according to phase-in plans submitted by a number of manufacturers. For the few that are 

produced, the staff estimates that in meeting the previous monitoring requirements, emissions 

Very likely would "remain below' 1751irf.es the ap'plicable"stahdards~as weir (probably even mdre 

likely than on current TLEV designs because LEV/ULEV catalyst system designs are expected 

to be more similar to the type described above for the Buick LeSabre test vehicle). The 

proposed requirement, however, would provide additional flexibility in designing catalyst 

monitoring approaches and would simplify the current regulatory requirements. 

Therefore, prior to the 1998 model year, the staff is considering the proposal to accept for 

TLEVs only, system monitoring based on an emission -threshold of 2.0 times the hydrocarbon 

standard plus the emission level using representative 4000 mile catalysts. This higher interim 

malfunction criterion should ensure that manufacturers able to meet the current front catalyst 

monitoring requirements on TLEVs will, with their present system designs, also be able to meet 

the revised requirements. If a manufacturer decides to satisfy these requirements with a 

monitoring strategy that infers total catalyst system performance through monitoring of a portion 

of the total catalyst volume, the ARB would not hold the manufacturer responsible for emission 

increases above the emission threshold resulting from damage fo unmonitored catalysts. 

3 
P.5 

conditions would lead to the fulfillment of the ARB's goals for this monitoring requirement while 

allowing manufacturers additional leadtime to address the technical concerns associated with 

the engine families for which misfire detection is most difficult. Specifically, the staff plans to 

propose a 50-75-90-100 percent phase-in schedule spanning from the 1997 model year 

through the 2000 model year. Small volume manufacturers would not be required to meet the 

phase-in percentages provided 100 percent implementation is achieved by the 2000 model 

year. 

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With respect to the scope of the monitoring conditions, the staff plans to propose maintaining 

the requirement for misfire detection during all engine speeds at positive torque loads with the 

exception of very light loads at engine speeds above 3000 rpm. Specifically, misfire detection 

disablement would be permitted in the operating region bound by the positive torque line (i.e., 

.tha.engine load'with--the-transmis9 

load at engine speed redline equivalent to the manifold vacuum at the positive torque line minus 

4 inches of mercury. This region is illustrated in figure 1. Manufacturers have stated that 

vehicle operation just above the positive torque line at high engine speeds represents the 

greatest challenge in terms of assuring reliable misfire detection. Further, the probability of 

'prelQrtged'vehicle'Operatio.ris'probaWyHowes^ -' 

proposal will better facilitate the implementation of expanded misfire detection monitoring 

conditions without significantly affecting air quality. 

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positive torque manifold vacuum - 4 inches Hg 

positive torque jneutra^^^Ldisablement area 

idle 1000 2000 3000 4000 

Engine Speed 

5000 redline 

Figure 1 -1997 and later model year misfire detection disablement region 

The ARB staff understands that some manufacturers may not presently be confident that the 

expanded misfire monitoring conditions, even with the permitted high speed, light load 

disablement, can be met on all of their engine designs. However, with the phase-in 

percentages proposed, manufacturers will have more development time to make 

enhancements, or to continue investigation of misfire detection technologies such as the 

magnetostrictive misfire detection sensor developed by Technical Advances, the fuel-on 

adaptive learning techniques developed by Purdue University, the advanced misfire detection 

4 
P.6 

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it may not be possible to reliably detect changes in emission control system performance before 

exceeding 1.5 times the standard. Regarding TLEVs, the staff has already approved the OBD 

II systems for two 1995 model year engine families. Data provided with the applications for the 

engine families indicate that malfunctions will be properly detected with respect to tailpipe 

emissions, thereby establishing the feasibility of implementing the OBD II thresholds on TLEVs. 

Of most concern would naturally be vehicles meeting the ULEV standards wherein the 

detection of a malfunction would be required before NMOG emissions exceed 0.06 grams per 

mile (i.e., before 50,000 miles). To date, the ARB has received very little data from the industry 

regarding the feasibility of meeting the emission thresholds for either ULEVs or LEVs. 

j^ow,@v§rJ'WtecUest^ it*vill. be possible^ implement-•;--? • 

the OBD II thresholds even on ULEV applications. 

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The testing conducted by the staff involved the introduction of simulated emission control 

system malfunctions or the installation of deteriorated components on prototype vehicles either 

-meeting oMomir^-elos@40'th©4JkE^ 

were tested. Results of the testing were presented during a panel discussion at the 1994 SAE 

Congress in Detroit. The testing is summarized below. 

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Regarding oxygen sensj^dete£0^ 

~in terms of response (measured by the period of the sensor at idle) or output voltage. A sample . 

- of the difference in oxygen sensor signals is provided in Figure 2. Figure 3 illustrates 

numerically the differences between "good" and "bad" sensors. The vehicles were tested to 

determine the resulting impact on emissions. While emission increases were noted 

(summarized.in Jable.1 \, the increjas§s,were„ppl£j^ emissions to ., ... -

exceed 1.5 times any of the ULEV standards, indicating that oxygen sensor deterioration should 

be detectable by OBD II systems on low-emission vehicles with respect to the 1.5 times the 

standard emission threshold. 

Table"! - Emission Results for Oxygen Sensor Testing 

Vehicle 

Le Sabre 

Jetta 

Corsica 

Camry 

NMHC (g/mi) 

0.028 

0.028 

0.039 

0.050 

0.037 

0,060 

0.044 

0.051 

CO (g/mi) 

0.261 

0.262 

0.675 

1.005 

0.423 

2.185 

0.688 

0.903 

NOX (g/mi) 

0.367 

0.404 

0.029 

0.013 

0.200 

0.053 

0.179 

0.193 

Test Condition 

Baseline Average 

Malfunctioning Sensor 

Baseline Average 

Malfunctioning Sensor 

Baseline Average 

Malfunctioning Sensor 

Baseline 

Malfunctioning Sensor 

To evaluate the impact of EGR system malfunctions, the staff installed restriction plates in the 

EGR passage to simulate malfunctions causing low EGR flow. With each of the test vehicles, a 

distinct difference in manifold pressure (see figures 4 and 5) was detected without emissions 

6 
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Figune 3 | J ? 

Ratio of Malfunction to Normal Voltage Characteristics of 0 2 Sensors During Idle After Closed Loop 

(During FTP Test 135-155 sec) for Various IJLEVs •'" 

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Figurel 5 

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Average Change in Manifold Air Pressure (MAP) Resulting from pulsed 

EGR During FTP Test (jCamry) . I 

(* .125" Dia EGR (96%) Restriction) 

I 

OEM EGR EGR Restricted* 

Point 1 Point 2 Point 3 

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13 

Diesel Applications 

In 1991, amendments were adopted to the regulation making the OBD II requirements 

applicable fo diesel engines beginning with the 1996 model year. Recognizing that some OBD 

II requirements would not apply, or could not be met on diesel applications, the regulation 

requires manufacturers of diesel engines to submit an OBD II monitoring plan for ARB review. 

After a number of discussions with manufacturers since the time diesels were included in the 

OBD II regulation, the staff believes enough has been learned to more specifically detail the 

minimum monitoring requirements for diesel applications. 

-3jrr .-TS. 

Generally, diesels are not equipped with evaporative systems, secondary air, or oxygen 

sensors. These monitoring requirements would, therefore, not apply. Regarding catalyst 

monitoring, the ARB has not yet identified a technology that can be put info production fo defect 

diesel catalyst deterioration. Catalyst monitoring is not currently proposed for diesels on this 

However, the ARB is proposing to require some form of misfire monitoring on diesel 

applications. It is recognized that diesel engines are not likely fo develop intermittent misfire 

problems as are spark ignited engines. Therefore, the staff currently believes it will be adequate 

forthe misfire detection strategy to be active only during certain operating conditions (e.g., 

during idle). The implementation of this requirement is proposed to begin with the 1998 model 

year. 

Regarding fuel system monitoring, manufacturej:s_.arej?u^entlyj§(Qrking .to implement .electronic, 

fuel delivery systems that provide feedback to the electronic control unit on fuel injection 

performance. Therefore, for electronic fuel systems on diesels, the staff believes that 

manufacturers will have the capability to meet the OBD II requirements to detect improper 

fueling before emissions exceed 1.5 times the applicable standards. 

OBD II monitoring strategies will be required for EGR system performance and for any 

'electronic components that can affect emissions"when"maTfunctioning(e.g., intake air heating, 

electronic transmission components, wait-to-start lamp, etc.). 

1996 Model Year Compliance 

At the July 9,1994, Board Hearing, the Board adopted amendments to the OBD II regulation to 

permit the certification of OBD II systems in the 1994 and 1995 model years with one or more .. 

deficiencies provided a good faith effort was demonstrated fo comply with the regulation in full. 

For 1995 models with more than two deficiencies, the manufacturer is subject to fines for the 

third and subsequent deficiencies. Currently, no provision exists for the certification of 1996 

OBD II equipped vehicles ifthe OBD II system is not in full compliance with the regulation. 

However, a few manufacturers have stated that one or possibly two specific engine families 

within their product lines are not likely to comply fully with the regulation for the 1996 model 

year. The difficulties encountered relate primarily to unexpected, recently decided product 

changes or extensions for which a particular monitoring requirement cannot be met in time for 

production. However, concerns regarding being able to implement a reliable monitoring 

strategy for certain emission control device designs or the value in major redesign of a model 

which has only one last year of life in 1996 have been presented as well. 

r 
P.10 

15 

Section (a)(2.0) would add that OBD II monitoring systems must be operative at a 

minimum at starting temperatures greater than 20 degrees Fahrenheit and at altitudes 

below 8000 feet above sea level. 

Section (a)(1.7) would add more specific approval criteria for the acceptance of alternate 

MIL illumination strategies. 

Br-scte'-.kacr "c ^ -c •i»-id»!W> •.--•na .--•• -*••»• •vv- •-?*••* 

Oxygen Sensor Monitoring 

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Section (b)(8.2.2) would more clearly state that a circuit continuity check is not sufficient 

for oxygen sensor heater monitoring. Oxygen sensor heaters are to be detected as 

~maJfunctioning-when-perforfnan<^fa.ls^ 

normal operation. 

Comprehensive Component Monitoring 

• "~"'"Section (b)(10) wou7d clarify that an electronic powertrain component must be monitored if 

it can measurably affect emissions during any reasonable operating condition (e.g., wide 

open throttle, idle, during reasonably cold ambient temperatures, etc.). 

• Seetion.(b)(10.2.1) would clarify thatjhe m^jmurr)JjinejDerrnitteQlfor eJosed-loop 

operation should be closely correlated to expected closed-loop activation times. The ARB 

expects manufacturers to employ malfunction criteria that are dependent on engine 

starting temperature and/or ambient temperature, which-should address often-stated 

concerns over avoiding false indications of a malfunction at colder starting temperatures 

while meeting the need for effective monitoring at more normal temperatures encountered 

in California. 

Other modifications are being considered to further clarify the intent of the comprehensive 

component monitoring requirements. 

MIL Illumination and Fault Code Storage Protocol 

Currently, illumination ofthe MIL is generally not required unless a malfunction is detected 

during two sequential trips. A trip is defined in part as a period of driving during which all 

components and systems are monitored at least once by the OBD II system. Therefore, if 

a specific monitoring strategy detects a malfunction in two sequential driving cycles, MIL 

illumination is not required unless all other (even non-related) monitoring strategies have 

operated during both of the driving cycles. The staff plans to propose a modification 

wherein MIL illumination would be required if a malfunction is detected in two sequential 

driving cycles regardless of whether or not other monitoring systems have functioned. 

However, manufacturers would still be permitted to verify the proper function of 

components critical to a particular monitoring strategy before the monitoring system 

operates or its results are validated. For example, execution ofthe catalyst efficiency 

monitoring strategy could still be delayed until the oxygen sensors used for monitoring are 

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. 
P.11 

17 

proposed for diesel vehicles because they normally do not employ closed-loop fuel 

control. 

Workshop informetion 

If any party wishes the information submitted to be treated as confidential by ARB staff, it 

should be clearly marked as "confidential" and should be on pages which are easily detachable 

from other, non-confidential, information. California guidelines (Sections 91000-91022, Title 17, 

California Code of Regulations, and Health and Safety Code Section 39660 (e)) will be followed 

in the handling of confidential information. 

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Manufacturers unable to participate in the workshop or those wishing to supply additional 

information are encouraged to submit written comments by July 23, 1994. Workshop 

participants wishing to discuss unresolved technical issues or confidential data may schedule 

Jndjy,idyaLme.eticig§ ,yyjJh.£taff.,. Please .contact Mj:.„Allen,Ly_onsTrAiraResources^ngineer -». - -

Associate, at (818) 575-6833 to schedule an individual meeting time and date. 

Sincerely, 

„j,» rfiftr »u*__* 

JS-"*. .*J~X. * . "> 

K. D. Drachand, Chief 

Mobile Source Division 

Attachment 

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P.12 

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ATTACHMENT 1 

1968.1 Malfunction and Diagnostic System Requirements-1994 and Subsequent Model-Year Passenger 

Cars, Light-Duty Trucks, and Medium-Duty Vehicles and Engines1 

(a) GENERAL REQUIREMENTS 

(1.0) All 1994 and subsequent model-year passenger cars, light-duty trucks, and medium-duty vehicles 

shall be equipped with a malfunction indicator light (MIL) located on the instrument panel that will 

automatically inform the vehicle operator in the event of a malfunction of any powertrain 

components which can affect emissions and which provide input to, or receive output from, the 

.jaifcboaKl.£<^puten(«)iQ^ shall not •*= ••-

be used for any other purpose. 

(1.1) The MIL shall be of sufficient illumination and location to be readily visible under all lighting 

conditions. The MIL shall illuminate in the engine-run key position before engine cranking to -

^ _ indjcatejthat.theJWjLjsj^nctkjnaljnd^^ g).e.Bh.caseJC.hjeck Engine"., 

or "Service Engine Soon". The word "Powertrain" may be substituted for "Engine" in the previous 

phrases. Alternatively, the International Standards Organization (ISO) engine symbol mav be 

substituted for the word "Engine" -

\ 

_, (12) _. _.AlU,9.94jand-SubsequeBtmodet-.year passangetc»rsT4ightr6luty-tFueksf.and»medium-duty vehicles 

required to have MIL pursuant to (1.0) above shall also be equipped with an on-board diagnostic 

system capable of identifying the likely area of the malfunction by means of fault codes stored in 

computer memory. These vehicles shall be equipped with a standardized electrical connector to 

provide access to the stored fault codes. Specific performance requirements are listed below. A 

(1.3) Any reference to vehicles in this regulation shall also include medium-duty vehicles with engines 

certified on an engine dynamometer. 

(4T4)—Manufacturers of diesel engines utilizing computer-based electronic powertrain control systems 

jhalj_3u_bmit,a p.ia_n for .complying with.the90.ccquiroment9io.theExecutivo Officer for approval ot 

least two years prior to certification. Tho plan ahall be approved based on monitoring all 

powertrain components which oan offcot cm.99ion3 and for which relioblc monitoring techniques 

erg available at costs comparable to other engines meeting those requirements, end on meeting 

all other applicable roquiromonts (e.g., storing freeze frame oonditions, mooting standardization 

requirements, eto.). 

ffc5)—For Low Emission Vehicles (LEV), the Executive Officer shall revise tho emission threshold for a 

malfunction on any chock if the mo9t reliable monitoring method developed requires a higher 

threshold to prevent significant errors of commission in detecting a malfunction. 

(1.64) For every case in which a malfunction is to be noted when an emission threshold is exceeded 

1

 The modifications indicated to this section are draft proposed changes for the purposes of 

discussion with respect to the OBD II workshop scheduled for July 27,1994. Deletions to the section are 

indicated by otrikoout and additions are indicated by underline. 

1 

. 

H 
P.13 

(2.0) Manufacturers mav disable monitoring svstems that can be affected bv running out of fuel (e.g.. 

misfire detection) when the fuel level is low, provided the manufacturer demonstrates that such 

disablement will onlv occur when the remaining driving range (i.e.. without refueling) is less than 

40 miles. 

(b) MONITORING REQUIREMENTS 

(1.0) CATALYST MONITORING 

(1.1) Requirement: 

(1.1.1) LEVs: Tho diagnostic system shall individually monitor the front catalyst or catalysts (i.e., 

any catalyst(9) which receive engine-out untreated oxhoust gas), except that front catalysts 

may be monitored in combination with the next catalyst downstream if it can be 

demonstrated that o malfunction will bo indicated when thc front catalyst .9 alone 

malfunctioning (see (b) (1.2.1)). Cotolysts arranged in parallel with the same inlet and outlet 

in a 9inglo exhoust pipo shall be considered as ono catalyst. A separate catalyst 

incorporated in series into the same container as a front catalyst shall bo oonsidered-e 

downstream catalyst. The diagnostic system shall monitor the catalyst system for proper 

performance, 

f~ r- • *r«-, «e — 

(1.1.2)—If tho front catalyst is a small volumo catalyst (see (b)(1.2.2)), tho diagnostic system ohall 

also monitor the next catalyst downstream of the small volumo cotalyst either independently 

of, or (ifthe conditions in section (1.1.1) are met) in combination with, thc small volume 

catalyst. 

(1A .3)r Manufacturers may submit other m^ltoTln^stratdgrcs; oubject to Executive Officer approval;" 

based on equal timeliness and reliability in detecting a catalyst malfunction as th09e 

requirements. 

(1.1.4)—Non-LEVs: Tho diagnostic system shall monitor thecatalyst system for proper performance. 

^_ LLL21 J/lanufacturers arejnot reouiredjo implement thgse catalyst monitoring requirements on 

dieseTvehicle's; and engines. 

(1.2) Malfunction Criteria: 

(1.2.1) LEVs: Each monitored catalyst, or combination of catalysts, shall be considered 

malfunctioning when ovorogc Federal Test Procedure (FTP) total hydrocarbon (HG) 

conversion efficiency falls between 50 to 60 percent. Tho efficiency determination oholl bo 

bosod on an FTP test wherein a malfunction is noted when thc cumulotivo total HC 

emissions measured at tho outlet ofthe monitored catalyat(s) is more than 40 to 50 percent 

of the cumulative total engine-out emissions measured at the inlet of the cotalyst(3). In 

addition, if a front catalyst is monitored in combination with a downstream catalyst, the front 

catalyst shall be considered malfunctioning when its efficiency has deteriorated between 40 

to 50 percent from its 4000 mile average FTP total HC efficiency. The catalyst system shall 

be considered malfunctioning when its conversion capability decreases to the point that 

either of the following occurs: 1. Non-Methane Hydrocarbon (NMHC. emissions exceed 1.5 

times the standard, or 2. the average Federal Test Procedure (FTP. NMHC conversion 

efficiency of the monitored catalyst or catalysts falls below 50 percent. With respect to the 

/ Z -

• 
P.M 

medium-duty vehicle operating conditions between 20 and 50 mph steady speed conditions 

with a load equivalent to 50 percent of the maximum load carrying capacity, (ii) take no more 

than a 20 second interval to determine both that the vehicle is operating in a proper window 

to perform the check and to actually perform the check, and (iii) be conducted at the earliest 

such condition encountered after the beginning of closed-loop operation for each driving 

cycle. Performance of the check may be delayed after engine startup until stabilized coolant 

temperature is achieved and/or a suitable cumulative time Interval of non-closed throttle 

vehicle operation has elapsed to ensure the catalyst is warmed-up for properly performing 

the monitoring check. The specified cumulative time interval shall begin from the first 

non-closed throttle operation either after achieving a stabilized coolant temperature or after 

engine starting and shall not exceed 180 seconds. These monitoring constraints and 

conditions may be altered, subject to Executive Officer Approval. Such approval shall be 

..Vnm^.-,-*,-^9^e^Uln^ra^»-^Q-a^ 

for the exception and demonstrates that the requested alteration would yield improved 

catalyst monitoring. "Reasonably steady" speed interval in this instance means a 20 second 

period where all accelerations and decelerations are of an average magnitude equivalent to 

0.5 mph/second or less over any two second interval during this period. The manufacturer 

J5SL2S2!tS_2SS!^^ 

vehicle exceeds the speed or acceleration/deceleration tolerances before the end of the 

checking interval. The manufacturer may base performance of the catalyst check upon 

engine RPM and toad conditions equivalent to the above monitoring conditions. If a 

manufacturer develops a means of monitoring catalyst efficiency which cannot utilize a 

...stead^jtateuroo.Ditoj^ •— -—> ~-

warmup), it may present a monitoring proposal to the Executive Officer for approval based 

on equivalent accuracy and timeliness as the steady state monitoring protocol in detecting a 

malfunctioning catalyst. 

«i*T«*.<'V>*1.(* 

(1.4) MIL Illumination and Fault: Cocle' Storage: "'** """ " "* """""""" 

(1.4.1) Except as noted below, upon detection of a catalyst malfunction, tho diagnostic system shall 

store Q fault code ond tho MIL-shall bo illuminated no later than the end of tho fioxt trip if tho 

malfunction is again present, upon detection of a catalyst malfunction, the MIL shall 

illuminate and a fault code stored no later than the end of the next driving cycle during which 

.monitoring occurs provided the malfunction is aoain present. . _ . . . _ .. 

(1.4.2) For steady state catalyst efficiency checks, upon detection of catalyst efficiency below 60 

percent, the diagnostic system may perform up to two successive monitoring checks prior to 

informing the vehicle operator of a malfunction. These monitoring checks need not occur on 

the same driving cycle, but shall be performed as soon as proper monitoring conditions 

occur. If catalyst efficiency remains below 60 percent for the three sequential checks, a fault 

code shall be stored and the MIL shall then be activated. 

(1.4.3) The diagnostic system shall temporarily disable catalyst monitoring when a malfunction 

exists which could affect the proper evaluation of catalyst efficiency. 

(1.4.4) The monitoring method for the catalyst(s) shall be capable of detecting when a catalyst 

trouble code has been cleared (except diagnostic system self-clearing), but the catalyst has 

not been replaced (e.g., catalyst overtemperature approaches may not be acceptable). 

(2.0) HEATED CATALYST MONITORING 

/ > 
P.15 

jurMflno****"*- «o»*»«tJ«fw*'"«Mtn «*««#.IKI 

(2.4.1) Upon detection of a catalyst heating malfunction, thc diognostic system shell store a fault 

code and the MIL shall be illuminated no later than the end of thc next trip if thc molfunction 

is again present the MIL shall illuminate and a fault code stored no later than the end of the 

next driving cycle provided the malfunction is again present. 

(2.4.2)—For hoatod catalyst efficiency malfunctions, tho MIL shall be illuminated, ond a fault code 

stored according to section (b) (1.4). 

(3.0) MISFIRE MONITORING 

(3.1) Requirement: The diagnostic system shall monitor engine misfire and shall identify the specific 

cylinder experiencing misfire. If more than one cylinder is misfiring, a separate code shall indicate 

is optional, however, identifying only one misfiring cylinder shall not occur when a multiple misfire 

code is stored). 

(3.2) Malfunction Criteria: The manufacturer shall specify in the documentation provided for certification 

,_j^e»s.gb.sect!©n4g).and.(ii^ 

necessary for determining a malfunction for each of the conditions listed below. 

(A) The percent misfire evaluated in 200 revolution increments for each engine speed and load 

condition which would result in catalyst damage. The manufacturer shall submit in the \ 

'-^ertificatien-doeumentation-catalysttemperature^data^ersus-percent misfire"overthe full— ~' 

range of engine speed and load conditions. The data shall be obtained from a representative 

cross section of a manufacturer's engine offerings from small to large displacements. Up to 

three such engine evaluations shall be documented per manufacturer, though a 

manufacturer may submit more data if desired. An engineering evaluation shall be provided 

^ ^ for estebjishing rngfunptipn crite^ 

product line. The Executive Officer shall waive the evaluation requirement each year if, in 

the judgment ofthe Executive Officer, technological changes do not affect the previously 

determined malfunction criteria; 

(B) The percent-misfire evaluated in 1000 revolution increments which would cause emissions 

from a durability demonstration vehicle to exceed 1.5 times any of the applicable FTP 

_„ _—standards-if the degree of misfire-were present from the beginning of the test. If the level ofmisfire determined under this requirement is significantly lower for an LEV as opposed to a 

Non-LEV with a similar engine design, the manufacturer may request approval from the 

Executive Officer to use a higher percentage of misfire as the malfunction criteria for the 

LEV, not to exceed the level of the Non-LEV. For the purpose of establishing the percent 

misfire, the manufacturer shall conduct the demonstration test(s) with the misfire events 

occurring at equally spaced complete engine cycle intervals, across randomly selected 

cylinders throughout each 1000 revolution increment. However, the percent misfire 

established shall be applicable for any misfire condition (e.g. random, continuous, equally 

spaced, etc.) for the purpose of identifying a malfunction. This criterion shall be used for all 

. .. vehicles with engines containing the same number of cylinders as the demonstration vehicle. 

The number of misfires in 1000 revolution increments which was determined for the durability 

demonstration vehicle malfunction criterion may be used to establish the corresponding 

percent misfire malfunction criteria for engines with other numbers of cylinders. The 

malfunction criteria for a manufacturer's product line shall be updated when a new durability 

demonstration vehicle is tested which indicates more stringent criteria are necessary than 

previously established to remain within the above emission limit; 

. 

H 
P.16 

UJ 

y tz?.. .-AVISE??! *~**%<oiz^^i^^2&4^^ 

• -;» ^*c.;^ct»v^.-.wpiv ...*•- asr c •• 

positive torque manifold vacuum - 4 inches Hg 

r>o-,£v>!f*C3's v'**w**"<*.tff«'*e«^vi9&gwj^^ *__..i.^i!^w5v<^r*il9D 

positive torquefneutaO^^^^^.^g^ 

j^-ry^c'^-mnirr-.t »i'-ar.'^*v«iMCS'**'-TV." . cptRwX^ ^ 

^jSJBJI&'ErfCfcfcB*..' •. «ST^7-JS*s>-«-3.^-*p-vc'JP' **>3^.^? : 

Idle 1000 2000 3000 . 4000 

Engine Speed . 

5000 redline 

•***«_., - ".**_, . . 

octaotMtr'''*^.'-'- >»c*- < 

(3.4) MIL Illumination and Fault Code Storage: 

(3.4.1) 

(3.4.2) 

(3.4.3) 

Except as provided below, upon detection ofthe level of misfire specified in subsection (3.2) 

' (A), the MIL shall blink once per second duringTctulllhi^fire TOnditiohs~ancl>emain 

continuously illuminated otherwise. In vehicles which provide fuel shutoff and default fuel 

control to prevent overfueling during misfire conditions, the MIL need not blink and may 

instead illuminate continuously upon detection of misfire provided that the fuel shutoff and 

default control shall be activated as soon as misfire is detected. Fuel shutoff and default fuel 

control may be deactivated only to permit fueling outside of the misfire range. 

Upon detection of the misfire levels specified in subsection (3.2) (B) or (C), the MIL shall be 

illuminated and a fault code stored no later than the end of the next driving cycle in which 

misfire is detected, unless driving conditions similar to those under which misfire was 

originally detected have been encountered (see section (3.4.3)) without an indication of 

misfire, in which case the initial temporary code and stored conditions may be erased... 

Furthermore, if similar driving conditions are not encountered during 80 trips subsequent to 

the initial detection of a malfunction, the initial temporary code and stored conditions may be 

erased. 

Upon detection of misfire, manufacturers shall store the engine speed, load, and warm-up 

status (i.e., cold or warmed-up) under which the first misfire event was detected. A trip or 

driving cycle shall be considered to have similar conditions if the stored engine speed 

conditions are encountered within 375 rpm, load conditions within 10 percent, and the same 

warm-up status is present. With Executive Officer approval, other strategies for determining 

if similar conditions have been encountered may be employed. Approval shall be based on 

comparable timeliness and reliability in detecting similar conditions. 

/ > ' 
P.17 

)»:» > (VHJ J W;*i«J*«a*t.l7v. . nar^9.KfUL..9*t99' 

system excluding the tubing and connections between the purge valve and the intake 

manifold. 

(4.2.2) Beginning with the 1998 model year, manufacturers shall phase-in diagnostic strategies to 

detect system leaks greater than or equal in magnitude to a leak caused by a 0.020 inch 

diameter orifice. The phase-in percentages (based on the number of evaporative families) 

shall equal or exceed 50 percent for the 1998 model year. 75 percent for the 1999 model 

year, and 100 percent implementation for the 2000 model year, Small volume manufacturers 

shall not be subject to the phase-in requirements: however. 100 percent implementation shall 

be reouired for 2000 model vear. 

(4.2.3) On vehicles with fuel tank capacity greater than 25 gallons, the Executive Officer shall revise 

ihefsize.ot,the.orifice.if.;the.mo^^^ 

system leak of thts thg magnitudes indicated above. 

(4.3) Monitoring Conditions: Thc monitoring system shall monitor thc ovaporativo system ot least onco 

per trip. Manufacturers shall define appropriate operating conditions for monitoring, subject to the 

liTMtetionJJhjaUhe_moj^ shalj be^nqountered at.least once duringJhe-first-engine 

"start portion of the applicable FTP test. The monitoring system shall operate at least once per 

driving cycle during which the manufacturer-defined monitoring conditions are met. However, 

monitoring conditions may be further constrained with respect to detecting leaks equivalent to a 

0.020 inch diameter orifice, subject to Executive Officer approval, on the basis that the monitoring \ 

conditions will.be.reasonabiy.HQCcurrinQ Jnr.use..and^>p&vided.that4hcheck-for leaks equal orareater•-

in magnitude than a 0.040 inch orifice will continue to be conducted at least once per driving cycle 

as indicated above. Subject to Executivo Officer approval, if performance of tho check causes 

vehicles to exceed applicable emission standards when using the best available technology; 

manufacturers may perform evaporative system monitoring during a steady-speed condition, as 

defined in section (b) (1.3.2), between 20 and 50 mph. 

."-.JB.-V ,*.<ie3tXL.>'» 

(4.4) MIL Illumination and Fault Code Storage: 

(4.4.1) Upon detection of an evaporative system malfunction or a malfunction that prevents 

completion of.an evaporative system check, the MIL shall illuminate and a fault code shall be 

stored no laterthan the end of the next driving cvcle during which monitoring occurs provided 

{he malfunction is again present, the-diagnostio system shall store a fault code ond the MIL 

shall illuminate no later than tho ond of tho next trip if the molfunotion is agoin detected, 

(4.4.2) If the diagnostic system is capable of discerning that a system leak is being caused by a 

missing or improperly secured fuel cap, the manufacturer may notify the vehicle operator 

through the use of an indicator light other than the MIL. The manufacturer is not required to 

store a fault code in this case. The indicator light shall conform to the requirements outlined 

in section (a) (1.1) for location and illumination. As another option, the manufacturer may 

extinguish the MIL, provided no other malfunctions have been detected, and may erase the 

fault code corresponding to the problem once the on-board diagnostic system has verified 

that the fuel cap specifically has been securely fastened. Other equivalent strategies shall 

be considered by the Executive Officer. 

(5.0) SECONDARY AIR SYSTEM MONITORING 

(5.1) Requirement: Any vehicle equipped with any form of secondary air delivery system shall have the 

diagnostic system monitor the proper functioning of (i) the secondary air delivery system and (ii) 

any air switching valve. 

11 

/fr 
P.18 

i >C** *J^*:«<»^ • •rfK'* W » «_«..*s* 

cycle during which monitoring occurs provided the malfunction is again present. The diagnostic 

system shall not clear a fault code and the MIL shall not turn off unless the leak has been 

corrected. 

(7.0) FUEL SYSTEM MONITORING 

(7.1) Requirement: The diagnostic system shall monitor the fuel delivery system for its ability to provide 

compliance with emission standards. 

(7.2) Malfunction Criteria: The manufacturer shall establish malfunction criteria to monitor the fuel 

delivery system such that a vehicle's emissions would not exceed 1.5 times any ofthe applicable 

FTP standards before a fault is detected. If the vehicle is equipped with fuel trim circuitry, the 

ffiiLn,ula£tuce^ 

has used up all of the trim adjustment allowed within the manufacturer's selected limit(s). 

Manufacturers may compensate the criteria limit(s) appropriately for changes in altitude or for 

temporary introduction of large amounts of purge vapor or for other similar identifiable operating 

conditions when they occur. 

»*«jci«tf"crT.:.ri'Er"-" \ ':i «.*«; ZL. ' ••a.":?"* **••" UJHTEF•!••"*• -HS.~«t-i'xry**^--. . 

(7.3) Monitoring Conditions: The fuel system shall be monitored continuously for the presence of a 

malfunction. 

(7.4) MIL Illumination and Fault Code Storage: 

(7.4.1) For fuel systems with short-term trim only capability, the diagnostic system shall store a fault 

code after the fuel system has attained the criteria limit for a manufacturer-defined time 

interval sufficient to determine a malfunction. If the malfunction criteria limit and time interval 

are exceeded, the MIL shall be illuminated and a fault code stored no later than the end of 

the next driving cycle in which the criteria and interval are again exceeded, unless driving 

- - •-- -- - ^conditions similartd' those 'under which th(_Tprobfem*wa1sIbTiginaTly 

encountered (see section (7.4.3)) without such an exceedance, in which case the initial 

temporary code and stored conditions may be erased. Furthermore, if similar driving 

conditions are not encountered during 80 trips subsequent to the initial detection of a 

malfunction, the initial temporary code and stored conditions may be erased. 

(7.4.2) For fuel systems with long-term fuel trim capability, upon attaining a long-term based 

malfunction criteria limit independent of, or in combination with, the short-term trim system 

status, the MIL shall be illuminated and a fault code stored no later than the end ofthe next 

trip driving cycle in which the malfunction is again detected, unless driving conditions similar 

to those under which the problem was originally detected have been encountered (see 

subsection (7.4.3)) without an indication of a malfunction, in which case the initial temporary 

code and stored conditions may be erased. Furthermore, if similar driving conditions are not 

encountered during 80 trips subsequent to the initial detection of a malfunction, the initial 

temporary code and stored conditions may be erased. 

(7.4.3) Upon detection of a fuel system malfunction, manufacturers shall store the engine speed, 

load and warm-up status (i.e., cold or warmed-up) under which the malfunction was 

detected. A trip or driving cycle shall be considered to have similar conditions if the stored 

engine speed is encountered within 375 rpm, load conditions within 10 percent, and the 

same warm-up status is present. With Executive Officer approval, other strategies for 

determining if similar conditions have been encountered may be. employed. Approval shall 

be based on comparable timeliness and reliability in detecting similar conditions. 

13 

>7 
P.19 

(8.3.1) For primary oxygen sensor(s) used for fuel control, the response rate and output voltage 

shall be monitored for malfunction before the end of the first idle period after the vehicle has 

commenced closed-loop operation, if the necessary checking condition for acceptable 

oxygen sensor(s) performance has been encountered. The performance of the sensor can 

only be judged acceptable by one or more of the following means: within any 20 second 

reasonably steady speed condition as defined in (b) (1.3.2), within any deceleration of 3 

seconds or more, or during the first idle period of at least 20 seconds after closed loop 

operation begins (i.e., not during an acceleration condition); not withstanding, unacceptable 

performance can be determined at any time. Other monitoring conditions may be used 

provided the manufacturer provides a monitoring strategy and supporting data showing 

equivalent monitoring reliability and timeliness in detecting a malfunctioning sensor 

compared to the above monitoring conditions and the Executive Officer approves. 

. » . •« tn,«»_^>n n v.<iar*-»«<B_n4H)'.-<Mm> «_».»ra__r«*.^««^ •-»i*BB»-^^ *K».m* ~f*V-, j»«y%s»»^^i»-«».: • 

t_i -z-- -a**?.*- -

(8.3.2) For secondary oxygen sensors used for catalyst monitoring and/or fuel system trim, the 

manufacturer shall define appropriate operating conditions for response rate and/or output 

voltage malfunction monitoring shall bo monitored for malfunction, subject to the limitation 

that the monitoring conditions shall be encountered at least once during the first engine start 

portion of the applicable FTP test. The monitoring system shall operate at least once per 

driving cycle during which the manufacturer-defined monitoring conditions are met eef-trip. 

(8.3.3) For heated oxygen sensors, the manufacutrer shall define appropriate operating conditions . 

fonpalfunctiqn monitoring of the heater circuit ahall •bc.monitored.for malfunction-subject to i 

the limitation that the monitoring conditions shall be encountered at least once during the first 

engine-start portion of the applicable FTP test. The monitoring system shall operate at least 

once per driving cvcle during which the manufacturer-defined monitorino conditions are met 

peHrip. 

- -^ (8:4)"" MIL Illumination and Fault Code Storage: Upon detection of aWyoXyg'eiTserTsor malfunction, the 

diagnostic system shall store a fault code and the MIL shall illuminate no later than the end of the 

next trip if thc malfunction is again present driving cycle during which monitoring occurs provided 

the malfunction is again present. 

(8.5) Other (non-lambda) Oxygen Sensors: . 

"~* ~i(8.5.1)" For vehicFes equipped with universal exhaust gas oxygen sensors (i.e. sensors which 

provide an output proportional to exhaust gas oxygen concentration), the manufacturer shall 

define appropriate operating conditions for the diagnostic system shall provide to perform a 

response rate check (the time required to respond to a specific change in fuel/air ratio),. 

subject to the limitation that the monitoring conditions shall be encountered at least once 

during the first engine start portion ofthe applicable FTP test. The monitorino system shall 

operate at least once per driving cycle during which the manufacturer-defined monitorino 

conditions are met, per trip and an The diagnostic system shall also perform an out-of-range 

check for which monitoring shall be continuous. For malfunctions, MIL illumination and fault 

code storage shall be as in (8.4). 

(8.5.2) If a manufacturer utilizes other types of oxygen sensors, the manufacturer shall submit a 

monitoring plan to the Executive Officer for approval based on equivalent monitoring with 

conventional sensors. 

(9.0) EXHAUST GAS RECIRCULATION (EGR) SYSTEM MONITORING 

15 

yr 
P.20 

(P)(C) The coolant temperature sensor shall be monitored for achieving a stabilized minimum 

temperature level which is needed to achieve closed-loop operation within a 

manufacturer-specified time interval after starting the engine. The Executive Officer shall 

allow disablement of this check under extremely low ambient temperature conditions 

provided a manufacturer submits data demonstrating non-attainment of a stabilized 

minimum temperature. 

(10.1.2) Output Components: 

(A) The diagnostic system shall monitor output components for proper functional response to 

computer commands, for proper functional response to each computor command, any powertrain 

output component/system receiving commands from the computer cither directly or indirectly 

above monitoring requirements. 

(B) Components for which functional monitoring is not feasible shall be monitored, at a minimum, for 

proper circuit continuity and out of range values, if applicable. 

(C) Output components may include, but are not limited to, the automatic idle speed motor, 

emission-related electronic only transmission controls, heated fuel preparation systems, thewaitto-start lamp on diesel applications, and a warmup catalyst bypass valve (see section (b) (10.5)), 

i 

... .I10?)J^alfanctionJ^riteriaL 

..- ' JJ - --*:_- r -x. . 

(10.2.1) Input Components: Input components/systems shall be considered malfunctioning when, 

at a minimum, lack of circuit continuity or manufacturer-specified out-of-range values 

occur. Additionally, the coolant temperature sensor shall be considered malfunctioning if it 

does not achieve a stabilized minimum temperature necessary for closed-loop operation 

""" ' within~a mariufacturer-sp'ecifigd time intervalIffirsfart^ " 

shall be a function of starting engine coolant temperature and/or a function of intake air 

temperature. Manufacturers shall provide data to support the times specified. 

(10.2.2) Output Components: Output components/systems shall be considered malfunctioning 

when.e proper functional response to eeeh computer commands does not occur. Should a 

Junctional cjiedcformajfancjio be 

considered malfunctioning when, at a minimum, lack of circuit continuity or 

manufacturer-specified out-of-range values occur. 

(10.3) Monitoring Conditions: Compononts/systoms in this subsection shall bo monitored continuously. 

(10-3.1) Input Components: Input components shall be monitored continuouslv for proper range of 

values and circuit continuity. For rationality monitoring (where applicable), manufacturers 

shall define appropriate operating conditions during which monitoring shall occur, subject 

to the limitation that the monitoring conditions shall be encountered at least once during the 

first start engine portion of the applicable FTP test. Rationality monitorino shall occur at 

least once per driving cvcle during which the manufacturer-defined monitorino conditions 

aESJDSL 

(10,3,2) Output Components: Monitoring for circuit continuity and proper ranee of values (if 

applicable) shall be conducted continuously. For functional monitoring, manufacturers 

shall define appropriate operating conditions during which monitorino shall occur, subject 

to the limitation that the monitoring conditions shall be encountered at least once during the 

17 

. / * 
P.21 

;r.»nni*T'ii>»-jv.X'W» VM-WI*-*** ? 

code system (e.g. EEPROM) shall include proven write-protect features which may include 

copyrightable executable routines or other methods. 

(e) READINESS/FUNCTION CODE If a full diagnostic check (i.e., the minimum number of checks 

necessary for MIL illumination) of all monitored components and systems has not been completed 

since the computer memory was last cleared, the manufacturer shall store a code indicating the need 

for additional mixed city and highway driving to complete the check. The code shall be stored in the 

format specified by SAE J1979 which is incorporated by reference in section (k)(2.0). The diagnostic 

system check for continuous monitoring of misfire and fuel system faults shall be considered complete 

for purposes of determining the readiness indication if malfunctions are not detected in these areas by 

the time all other diagnostic system checks are complete. If monitoring is temporarily disabled under 

conditions which may lead to false codes for any system, that check shall not be considered in 

,d.e.terj£Jflins,dLaanj?.^ 

acknowledge message indicating that the diagnostic system itself is functioning properly. 

*ijJ^J5-*£-*».•*•'•= 

(f) STORED ENGINE CONDITIONS Upon detection of the first malfunction of any component or 

system, "freeze frame" engine conditions present at the time shall be stored in computer memory. 

Should a subsequent fuel system or misfire malfunction occur any previously stored freeze frame 

conditions shall be replaced by the fuel system or misfire conditions (whichever occurs first). Stored 

engine conditions shall include, but are not limited to, calculated load value, engine RPM, fuel trim 

. value(s), fuel pressure (if available), vehicle speed (if available), coolant temperature, intake manifold 

pressure (if available), closed- or open-loop operation, and the fault code which caused the data to be 

..-.,.-,,stg/ed.^hej^ x . 

repairs for freeze frame storage. Only one frame of data is required. Manufacturers may at their 

discretion choose to store additional frames provided that at least the required frame can be read by a 

generic scan tool meeting SAE specifications established in SAE Recommended Practices on "OBD II 

Scan Tool" (J1978), March 1992, and "E/E Diagnostic Test Modes" (J1979), December 1991, which 

are incorporated by reference herein. Ifthe fault code causing the conditions to be stored is erased in 

' accordance with section (c)' (3.0)rthe storeiTerigfrie^ori'ditio^ 

(g) DURABILITY DEMONSTRATION VEHICLE 

(1.0) REQUIREMENT Each year a manufacturer shall provide emission test data obtained from a 

. certification durability vehicle fdr one engine family certification durability vohielo that has not been 

u s ^ previously for purposes of this section. If a manufacutrer does not have a certification. 

durability vehicle available which is suitable for this demonstration, Tthe Executive Officer shall 

permit a manufacturer to satisfy this reouirement with waive this requirement if a manufacturer 

does not havo a certification durability vehicle available which is suitable for this demonstration in 

a given year, provided a manufacturer submits other data from a representative high mileage 

vehicle or vehicles (or a representative high operating-hour engine or engines) acceptable to the 

Executive Officer to demonstrate that malfunction criteria are based on emission performance. 

The Air Resources Board (ARB) shall determine the demonstration vehicle engine family to be 

demonstrated. Each manufacturer shall notify the Executive Officer prior to running a California 

durability vehicle in order to allow possible selection as the demonstration vehicle for a given 

model year unless a vehicle has previously boon chosen for the given model year applying for 

certification of the engines families planned for a particular model year in order to allow selection 

of the engine family to be demonstrated. Demonstration tests shall be conducted on the 

certification durability vehicle or engine at the end of the required mileage or operating-hour 

accumulation. For non-LEVs, until a NOx standard applicable fbr more than 50,000 miles is 

established in California, the federal 50,000 to 100,000 mile NOx standard shall be used for 

demonstration purposes. 

19 

JO 

. 
(2.6) Catalyst Efficiency: 

(2.6.1) Non-LEVs: The manufacturer shall conduct a baseline FTP test with a representative 

4000 mile catalyst followed by one FTP demonstration test using a catalyst system 

deteriorated to its malfunction limit. If a manufacturer is employing a steady state catalyst 

efficiency check in accordance with section (b) (1.2.4), demonstration of the catalyst 

monitoring system is not required. 

(2.6.2) LEVs: The manufacturer shall conduct a catalyst efficiency demonstration using a catalyst 

system deteriorated to withm the malfunction criteria. If two 3ub9tratcs aro integrated into 

tho some container, only tho upstream substrate shall be deteriorated for tho 

demonstration.-

„u_w .-_ .••-i*»_«(#<_<s*»__*».*i>ii*»*.'*>« ,s f t ^^ «•»-»«-« • ««»,^>r««Ba»«a»#~'a»»-^e»"«>MjaBano» ..--a»^>»e<^7««»taf3r»ia«l«a»a3»« .-,«KK*»-M»**.-..„-_BM»._~.-M«»«_ 0 ,»» < 

(2.7) Heated Catalyst Systems: For heated catalyst systems that uso an after start heating strategy; t 

The manufacturer shall conduct a demonstration test where the designated heating temperature is 

reached at the time limit for malfunction after engine starting. 

~~^r8)^~Mar^aetureraTMay^ectron.eatty^^ — 

vehicle control unit modifications when performing demonstration tests. All equipment necessary 

to duplicate the demonstration test must be made available to the ARB upon request. 

(3.0) PRECONDITIONING The manufacturer shall use the first engine start portion of one applicable; 

"FTP cycle 15"nrr¥eo"rtd1tlo*rirrtg"beW^eaCh~of thVab^v¥^rnissiorTfesB". "If a manufacturercan 

demonstrate that additional preconditioning is necessary to stabilize the emission control system, 

the .Executive Officer shall allow an additional identical preconditioning cycle, or a Federal 

Highway Fuel Economy Driving Cycle, following a ten-minute (or 20 minutes for medium duty 

engines certified on an engine dynamometer) hot soak after the initial preconditioning cycle. 

- *—•- vw> -nan*-'*•**- •••c "*5et>" -

(4.0) EVALUATION PROTOCOL 

(4.1) With the exception of short-term trim only vehicles, the manufacturer shall set the system or 

component at the criteria limit(s) from the beginning of and throughout the applicable 

preconditioning cycle and FTP test. 

(4:2) - For short-term trim only vehicles; the fuel system shaHoperate at the criteria limit from the 

beginning of closed-loop operation for the manufacturer-defined time interval for determining 

malfunction (and normally otherwise) for both the applicable preconditioning and FTP test cycles. 

(4.3) For misfire demonstration, misfire shall be set at its criteria limit as specified pursuant to section 

(b) (3.2) (B) throughout the applicable preconditioning cycle and FTP test. 

(4.4) For all demonstrations, the MIL shall be illuminated before the hot start portion of the FTP test in 

accordance with requirements of subsection (b): 

(4.4.1) If the MIL does not illuminate when the systems or components are set at their limit(s), the 

criteria limit or the OBD system is not acceptable. 

(4.4.2) Except for catalyst efficiency demonstration, if the MIL illuminates and emissions do not 

exceed 1.5 times any ofthe applicable FTP emission standards, no further demonstration 

shall be required. 

(4.4.3) Except for catalyst efficiency demonstration, if the MIL illuminates and emissions exceed 

21 

A( 
P.23 

ii. monitoring method or procedure for malfunction detection 

iii. primary malfunction detection parameter and its type of output signal 

iv. fault criteria limits used to evaluate output signal of primary parameter 

v. other monitored secondary parameters and conditions (in engineering units) necessary for 

malfunction detection 

vi. monitoring time length and frequency of checks 

vii. criteria for. storing fault code 

viii. criteria for illuminating malfunction indicator light 

ix. criteria used for determining out of range values and input component rationality checks 

(3) A logic flowchart describing the general method of detecting malfunctions for each monitored 

emission-related component or system. To the extent possible, abbreviations in Society of 

OC*^>-arai.^.** ,^r«^utomot ^ 

Abbreviations, and Acronyms", September, 1991, shall be used.'J1930 is incorporated by reference 

herein. The information required in the chart under (2) above may instead be included in this flow 

chart, provided all of the information required in (2) is included. 

^..„ „..,.{4)jyjs_tingJ^dJ?lock.d.iagr^ 

values and the input parameters used to calculate or determine fuel trim values. 

(5) A scale drawing of the MIL and the fuel cap indicator light, if present, which specifies location in the 

instrument panel, wording, color, and intensity. * 

,vi%*9-C^io.'j^t:. •• 

(6) Emission test data specified in subsection (g). 

(7) Data supporting the selected degree of misfire which can be tolerated without damaging the catalyst. 

(8)_patejsup|DojtingJ.heJimit for the.timej)etwejgn_engjn^sta.{li.ng-and.attaJningjthe designated heating .. 

"temperature for'after-start heated catalyst systems. 

(9) For LEVs, data supporting the criteria used by tho diagnostic system for establishing a 50 to 60 

percent catalyst total HC efficiency level, or a 40 to 50 percent deterioration level to indicate a 

malfunction when catalyst deterioration causes emissions to exceed 1.5 times the applicable HC 

standard, or the interim emission threshold specified in section (b)(1.2.1). whichever is applicable. 

(10) For Non-LEVs, data supporting the criteria used to indicate a malfunction when catalyst 

deterioration leads to a 1.5 times the standard increase in HC emissions. If a steady state catalyst 

efficiency check is employed in accordance with section (b)(1.2.4), data supporting the criteria 

used by the diagnostic system for establishing a 60 to 80 percent catalyst efficiency level shall be 

provided instead. 

(11) Data supporting the criteria used to detect evaporative purge system leaks. 

(12) A description of the modified or deteriorated component used for the fault simulation to drive the 

. fuel system to the criteria limit(s) for demonstrating fuel system compliance with the requirements 

of subsection (g). 

(12) A listing of all input and output signals for the engine and transmission control units. 

(134) Any other information determined by the Executive Officer to be necessary to demonstrate 

compliance with the requirements of this section. 

23 

JTX. 
r 

,*ZAI j***&-i»<«x\>i tpbavr Ke*«- ^ 

- it- r-_i ••»;rmrrr*» -' 

TT> _~a r. 

header, and shall not use inter-byte separation or checksums. 

(2.0) J1978 & J1979 Standardization ofthe message content (including test modes and test messages) 

as well as standardization of the downloading protocol for fault codes, parameter values and their 

units, and freeze frame data are set forth in SAE Recommended Practices on "OBD II Scan Tool" 

(J1978), March, 1992, and "E/E Diagnostic.Test Modes" (J1979), December, 1991, which have been 

incorporated by reference. Fault codes, parameter values, and freeze frame data shall be capable of 

being downloaded to a generic scan tool meeting these SAE specifications. 

(2.1) Manufacturers shall make readily available at a fair and reasonable price to the automotive repair 

industry vehicle repair procedures which allow effective emission related diagnosis and repairs to be 

performed using only the J1978 generic scan tool and commonly available, non-microprocessor 

-^^^-•"•^-•-•^^secl^ols^ n 

referencing the use of manufacturer specific or enhanced equipment. 

(2.2) The J1978 scan tool shall be capable of notifying the user when one or more of the required 

monitoring systems are not included as part of the OBD system. 

(3.0) J2012 Part C Uniform fault codes based on SAE specifications shall be employed. SAE 

"Recommended Format and Messages for Diagnostic Trouble Codes" (J2012), March, 1992, is 

incorporated by reference. 

K4^--^962-n^ster^ard-dataHii^coftrtectoHn-a standard-locationirreach-vehicle basedon'SAE'-- " — 

specifications shall be incorporated. The location of the connector shall be easily identified bv a 

technician entering the vehicle from the driver's side. Any pins in the standard connector that provide 

any electrical power shall be properly fused fo protect the integrity and usefulness of the diagnostic 

connector for diagnostic purposes. The SAE Recommended Practice "Diagnostic Connector" 

^_r^-„. (J.I962),.June, J.992, isJjncojporated,by_j^ ..^^ ..„.. _. . .=_.,. .„_. _ __„_» 

(5.0) Medium-duty vehicles may employ the communication protocols established in SAE Recommended 

Practice J1939 to satisfy the standardization requirements specified above as an alternative to the 

protocols established in SAE documents J1850. J1979. J2012. and J1962. 

(I) SIGNAL ACCESS 

(1.0) The following signals in addition to the required freeze frame information shall be made available on 

demand through the serial port on the standardized data link connector calculated load value, 

diagnostic trouble codes, engine coolant temperature, fuel control system status (open loop, closed 

loop, other), fuel trim (if equipped), fuel pressure (if available), ignition timing advance, intake air 

temperature (if equipped), manifold air pressure (if equipped), air flow rate from mass air flow meter 

(if equipped), engine RPM, throttle position sensor output value (if equipped), secondary air status 

(upstream, downstream, or atmosphere; if equipped), and vehicle speed (if equipped). The signals 

shall be provided in standard units based on the SAE specifications incorporated by reference in this 

regulation, and actual signals shall be clearly identified separately from default value or limp home 

signals. 

(2.0) The manufacturer shall publish in factory service manuals a normal range for the calculated load 

value and mass air flow rate at idle, and at 2500 RPM (no load, in neutral or park). Ifthe total fuel 

command trim is made up by more than one source (e.g. short-term trim and long-term trim), all fuel 

trim signals shall be available. The signals shall be provided in standard units based on the 

incorporated SAE specifications, and actual signals shall be clearly identified separately from default 

value or limp home signals. 

25 

a3 

Hull Ml I M 
P.25 

**.*---*-w>d*wr»-:*•#**•*-••»*• 

evaluating and considering the best available monitoring technology. 

(6.1) For 1995 model year vehicles for which production is to commence subsequent to March 31,1994, 

and which are not exempted from compliance in accordance with sections (2.0) and (2.1) above, the 

Executive Officer, upon receipt of an application from the manufacturer, may certify the vehicles in 

question even through said vehicles may not comply with one or more ofthe requirements of these 

subsections. Such certification is contingent upon the manufacturer meeting the criteria set forth in 

section (6.0) above. Manufacturers of non-complying systems shall be subject to fines pursuant to 

section 43016 of the California Health and Safety Code for each deficiency identified, after the 

second, in a vehicle model. For the third deficiency and every deficicney thereafter identified in a 

vehicle model, the fines shall be in the amount of $50 per deficiency per vehicle for non-compliance 

with any ofthe monitoring requirements specified in subsections (b)(1) through (b)(9), and $25 per 

determining the identified order of deficiencies, deficiencies of subsections (b)(1) through (b)(9) shall 

be identified first. Total fines per vehicle under this section shall not exceed $500 per vehicle and 

shall be payable to the State Treasurer for deposit in the Air Pollution Control Fund. Engine families 

in receipt of a waiver granted under section (6.0) above shall be exempt from these fines. Further, 

., ^...^..sroaJUoluroe^man.ufacturerstChQ inthe4995-model*yearTM—• - —<•>-

shall also be exempt from these fines. 

(6-2) For 1996 model year vehicles, the provisions set forth in section (m)(6,1) above shall also apply for 

up to three engine families. Intermediate volume manufacturers shall be limited to two such engine \ 

-^fami-iesT-and smaiWolume-mantifacturers shall-be-ttmited toone-sucfrenoine family. -With-respect to-- - - - — 

this section onlv. failure to properly monitor multiple electronic transmission components shall be 

considered a single monitoring system deficiency. 

(6.3) For 1.997 and later model years, vehicles with identified monitoring system deficiencies may be 

certified: howeverJh§ fines specifiecj in sectipn ,(m)(6.1) above shall apply to all identified monitoring 

system deficiencies. With respect to this section, manufacturers may not carry over monitoring 

system deficiencies to future model years. 

. (n) GLOSSARY For purposes of this section: 

.(.1.0.) .-"Malfunction'-'-meanstheinability of an emission-related-component or system to remain within 

design specifications. Further, malfunction refers to the deterioration of any of the above 

components or systems to a degree that would likely cause the emissions of an average certification 

durability vehicle with the deteriorated components or systems present at the beginning of the 

applicable certification emission test to exceed by more than 1.5 times any of the emission 

standards (both with respect to the certification and usefull life standards), unless otherwise 

specified, applicable pursuant to Subchapter 1 (commencing with Section 1900), Chapter 3 of Title 

13. 

(2.0) "Secondary air" refers to air introduced into the exhaust system by means of a pump or aspirator 

. valve or other means that is intended to aid in the oxidation of HC and CO contained in the exhaust 

gas stream. 

(3.0) "Engine misfire" means lack of combustion in the cylinder due to absence of spark, poor fuel 

metering, poor compression, or any other cause. 

(4.0) Oxygen sensor "response rate" refers to the delay (measured in milliseconds) between a switch of 

the sensor from lean to rich or vice versa in response to a change in fuel/air ratio above and below 

27 

*f 
P.26 

_ •* (15.0) "Diesel engines", for the purposes of these regulations, includes diesel derived engines and those 

using a compression ignition thermodynamic cycle. 

(16.0) "Functional check" for an output component means verification of proper response to a computer 

command. For an input component, functional check means verification of the input signal being in 

the range of normal operation, including evaluation of the signal's rationality in comparison to all 

available information. 

(17.0) "Federal Test Procedure" (FTP) cycle or test refers to, for passenger vehicles, light-duty trucks, and 

medium-duty vehicles certified on a chassis dynamometer, the driving schedule in Code of Federal 

Regulations (CFR) 40, Appendix 1, Part 86, section (a) entitled, "EPA Urban Dynamometer Driving 

Schedule for Light- Duty Vehicles and Light-Duty Trucks." For medium-duty engines certified on an 

«», w . x «»«». ^*^!L\$-l®-$t^^ schedule-in-GFR 40;.-

Appendix 1, Part 86, section (f)(1), entitled, "EPA Engine Dynamometer Schedule for Heavy-Duty 

Otto-Cycle Engines," or section (f)(2), entitled, "EPA Engine Dynamometer Schedule for 

Heavy-Duty Diesel Engines." 

^(18.0) "Redline engine speed" meajTsjhejnan^ g_nqi

ne

_ ?peed as. •,.. . _., 

' '-"'*"" J" "''i'

J

'horn^Trv"?ispTayeoi*6n instrument "panel tachometers.' 

29 

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